It is apparent that in recent years there has been an increased public awareness of the problems associated with the disposal of radioactive nuclear waste. Accordingly, significant measures have been taken to isolate and confine nuclear waste so that there is minimal harm to the public and to the environment. Much of this activity has resulted from the fact that the adverse effects of radioactivity are well known and well documented. It is also a fact, however, that many of the measures which have been taken heretofore for the disposal of nuclear waste have been, or are now, ineffective for their intended purpose.
It has been suggested that a solution to the nuclear waste problem is to separate the radionuclides from the non-radioactive particles in the waste. The object here has been to reduce the amount of material that requires special handling, and thereby simplify the disposal process. To dispose of nuclear waste in this manner, however, it is first necessary to vaporize the waste to create a multi-species plasma. Such a plasma will include charged particles of relatively high mass (the radionuclides are in this group), and charged particles of relatively low mass (the non-radioactive elements). As a practical matter, after the nuclear waste has been vaporized, the problem becomes one of effectively separating the higher-mass particles from the lower-mass particles in the plasma.
Plasma centrifuges, which operate in accordance with well known physical principles, have been shown to be capable of creating a distribution in which plasma particles are generally distributed according to their mass. In accordance with centrifuge techniques, charged particles will pass through the centrifuge under the influence of crossed electric and magnetic fields. They are then collected as they exit the centrifuge. As they transit the centrifuge, however, centrifugal forces cause the particles to cross the magnetic field lines which are established in the centrifuge by the magnetic field. Thus, the magnetic field lines resist movement of the charged particles. In turn, the separation of particles in a centrifuge is affected by this resistance. On the other hand, charged particles can move along, rather than across, magnetic field lines, with much less resistance.
It is known that for a charged particle of mass, m, traveling on a curved path having a radius of curvature, r, the centrifugal force F.sub.c acting on the particle can be expressed as: EQU F.sub.c =mr.omega..sup.2
where .omega. is the angular speed or frequency of rotation of the particle on the path. Further, it is known that a centrifugal force will act on a charged particle to urge the particle toward the outside of the curve on which the particle is traveling. Accordingly, and in light of the above discussion regarding magnetic field lines, if magnetic field lines can be oriented so that a centrifugal force will act generally in the same direction as the magnetic field lines, the particles can move freely along the magnetic field to adjust to the effect of the centrifugal force. Consequently, the centrifugal force can be made more effective for separating particles according to their respective masses.
In light of the above, it is an object of the present invention to provide a nuclear waste remediation system which effectively separates, segregates and isolates particles of a multi-species plasma according to the respective masses of the particles. Another object of the present invention is to provide a nuclear waste remediation system which is capable of accelerating all particles in a multi-species plasma to a common translational velocity in the straight section and a common rotational velocity in the curved separation section so that the various particles in the plasma can be separated from each other according to only the respective masses of the particles. A key element of the present invention is to provide a nuclear waste separation system which eliminates the opposing influence of the magnetic field to the separating influence of the centrifugal force on charged particles. Still another object of the present invention is to provide a nuclear waste remediation system which is simple to use, is relatively easy to manufacture, and is comparatively cost effective.